    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    <form  method="get">
        用户名：<input type="text" name="usr_name" />
        加密：<keygen name="security" /><!--        该标签已经废弃-->

        <input type="submit" />
    </form>
    </body>
    </html>